Okee-Dokee Brian, here goes:
Run the wire from the + post on the left side of the battery (There is a clamp on the post so use the screw that tightens the clamp). Run the wire from that around the air filter box if you have a Duratec. If it's a Zetec, head straight for the firewall. Now, you can either dril a hole like I did or run the wire under the windshield flashing. I found it quicker to drill, and I doubt it will affect the warranty unless your service department is full of jerks. I drilled through beside the clutch pedal, the firewall is empty on the other side. Now, make sure you put in a fuse within a foot of the battery that matches the fuse on your amplifier. You should be able to find the right rating in the amp's intructions. When you put it in, make sure yo pull the fuseso there is no power going through the wire while you are running itthrough the car. After you get the wire through the firewall, run it under the left door sill. Unscrew the sill and pull it away (you may want to remove the front seat) Be careful as there are clips around the screws and the like to break. Eventually, you'll come out under the back seat and into the trunk. Crimp an end connection to it (looks like a tiny two pronged fork) and attach it to the Amps + terminal. You are done the + side. Now run a - cable (Get a different color so as not to ever get confused in the future) from the - post to the ground.
Now for the RCA patch cables. I recommend getting a set of shielded cable to cut out engine noise. Dave or Aaron will have a good recommendation. Anyways, run the cables from the Sub Out (If your deck doesn't have one use the rear channels) pull them through the back of right side of the HU opening. Run them under the glove box under the kick panel (A piece of auto grade carpeting with a few clips holding it on) Now run it down the right side of the car. You can't just run it down the left side with the power cable, it will produce noise, which is bad! Again you will come out under the back seat. Connect it to the amp!
Now just put the fuse back in and you're done, hook up the sub and take it for a test spin! Hope I was helpful, good luck!
